Snow was being blown by winds gusting to 65km/h when the flight from Minneapolis carrying 76 passengers and four crew attempted to land on a dry runway on Monday afternoon.
Authorities said the cause of the crash remained under investigation.
Video posted to social media only showed the aftermath with the Mitsubishi CRJ-900LR overturned, the fuselage seemingly intact and firefighters dousing what was left of the fire as passengers climbed out and walked across the tarmac.
"We are very grateful there was no loss of life and relatively minor injuries," Deborah Flint, CEO of Greater Toronto Airports Authority, told reporters.
Toronto Pearson Fire Chief Todd Aitken said 18 passengers were taken to the hospital.
Earlier in the day, Ornge air ambulance said it was transporting one pediatric patient to Toronto's SickKids hospital and two injured adults to other hospitals in the city.
Tower controllers were heard speaking with the crew of a medical helicopter that had just left Pearson and was returning to help with the crash.
The plane came to a rest at the intersection of two runways, the controller said.
"Just so you're aware, there's people outside walking around the aircraft there," a tower controller said.
"Yeah, we've got it. The aircraft is upside down and burning," the helicopter pilot responded.
According to the Meteorological Service of Canada, the airport was experiencing blowing snow and winds of 50km/h gusting to 65km/h amid temperatures of minus 8.6C.
"It's very rare to see something like this," said John Cox, CEO of aviation safety consulting firm Safety Operating Systems in Florida.
"We've seen a couple of cases of take-offs where airplanes have ended up inverted, but it's pretty rare."
The audio recording from the tower at Toronto Pearson International Airport shows the flight was cleared to land just after 2.10pm.
The tower warned the pilots of a possible air flow bump in the glide path as the plane came in to land.
"It sounds to me like a controller trying to be helpful, meaning the wind is going to give you a bumpy ride coming down, that you're going to be up and down through the glide path," Cox said.
"But the airplanes are designed and certified to handle that. The pilots are trained and experienced to handle that."
US investigators will assist in the investigation by the Canadian transport safety officials.
This is at least the fourth major aviation mishap in North America in the past month.
A commercial jetliner and an army helicopter collided near Washington, DC, on January 29, killing 67 people.
A medical transportation plane crashed in Philadelphia on January 31, killing the six people on board and another person on the ground, and 10 were killed in a plane crash in Alaska.
Premier Doug Ford, the leader of Ontario province whose capital is Toronto, said he was "relieved there are no casualties after the incident at Toronto Pearson".
Delta CEO Ed Bastian said in a statement that "the hearts of the entire global Delta family are with those affected by today's incident at Toronto-Pearson International Airport".
Endeavor Air, based in Minneapolis, is a subsidiary of Delta Air Lines and the world's largest operator of CRJ-900 aircraft.
The airline operates 130 regional jets on 700 daily flights to more than 126 cities in the US, Canada and the Caribbean, according to the company's website.
